Russia’s new weapons buildup has attracted considerable attention in Washington. Yet to offer a fully coherent response, the U.S. should consider what exactly these weapons represent. As argued in a previous article, I believe these weapons – Avangard, Kinzhal, and Tsirkon – do not fundamentally alter the strategic balance between Washington and Moscow. They do, however, as dual-capable systems, moderately heighten the risk of miscalculation and accidental escalation. They also seem to represent the culmination of long-held Russian antipathy towards U.S. missile defense programs. If these assessments are accurate, there are several measures the U.S. should adopt to respond to Russia’s new weapons programs.
Recommendation #1: Don’t Overreact
With the new Russian systems adding little to Russia’s already mortifying ability to destroy the United States in a nuclear conflict, the U.S. should not overreact to the threat posed by these weapons. So far, it seems the U.S., and in some ways Russia, have wisely accepted that reality. The relatively easy slotting of Avangard into the existing New START framework has been encouraging. Wherever possible, existing arms control measures should be adapted to include newer systems. For instance, proposals for a post-New START arrangement could require weapons like Kinzhal to be placed only on treaty-accountable aircraft.1
Moreover, as the new systems do not substantially reduce reaction time to the extent some have feared, the U.S. should not race to mimic such systems in pursuit of faster delivery. While the U.S. may need hypersonic missiles for a variety of reasons, the faster speed of these systems should not in and of itself be a primary motivating factor in pursuing them. As impressively fast as Russia’s hypersonic missiles are, the U.S. already has its own impressively fast delivery mechanisms for nuclear missiles. If the U.S. were to pursue an increased hypersonic missile capability, it should consider pursuing conventional missiles only.
Recommendation #2: Reduce the Dual-Capable Problem Where Possible
Unlike other powers, the U.S. maintains a division between its conventional and nuclear missiles, refusing to put conventional weapons on its intercontinental ballistic missiles. In the absence of a similar commitment by other powers, including Russia, the U.S. runs the risk of misreading Russian signaling in advance of a crisis and mistaking an incoming Russian conventional weapon for a nuclear attack. The dual-capable nature of all three Russian systems should induce an attempt by the U.S. to obtain as strong a division between Russian conventional and nuclear missiles as possible.2
Given the high degree of investment and publicity Russia dedicated to these systems, it is highly unlikely Moscow would agree to an outright prohibition on their deployment. Nevertheless, working to craft any sort of prohibition on dual-capable systems is a cause well worth pursuing.
Given the high degree of investment and publicity Russia dedicated to these systems, it is highly unlikely Moscow would agree to an outright prohibition on their deployment. Nevertheless, working to craft any sort of prohibition on dual-capable systems is a cause well worth pursuing. Even if an outright prohibition on dual-capable systems proves unobtainable, greater transparency around which specific systems are equipped with nuclear warheads would be helpful. Unfortunately, as hard as it might be to obtain limits on dual-capable systems today, the difficulty is likely to increase in the coming years.
There is, however, still some cause for optimism. Like all the best arms control measures, limitations on dual-capable systems have the benefit of being verifiable. As physicist Dean Wilkening put it, “verifying that hypersonic weapons are not deployed with nuclear warheads is, in principle, possible with current techniques.”3 The U.S. should take advantage of this fact in future arms control negotiations with Russia while remaining realistic about Russian enthusiasm for limits on these systems.4 The U.S. could also try to lock in existing limitations on hypersonic missiles, such as enshrining a principle of no dual-use intercontinental missiles.5
Recommendation #3: Don’t Be Afraid To Discuss Missile Defense
Russia’s actions and statements over the years have made it clear that U.S. missile defense programs are a key driver of Russian behavior, specifically regarding its decision to develop weapons like Avangard, Kinzhal, and Tsirkon. Given the continued unreliability of strategic missile defense, the U.S. should be willing to put the discontinuation of some missile defense efforts on the table. Acknowledging that there are numerous other reasons for the U.S. to discuss limiting its missile defense programs,6 the U.S. should take comfort in the fact that discussing such limits would, if anything, diminish Russia’s costly interest in nuclear hypersonic systems.
To be clear, the U.S. does not have to agree to limits on its missile defenses upfront. Rather, the U.S. should be open to limiting its missile defenses as part of broader strategic stability talks with Russia. U.S. missile defense has largely driven the development of the new Russian systems, and the U.S. should not expect Russia to abandon them without curtailing their catalyzing impetus.7 Indeed, Russian arms control negotiator Alexei Arbatov hinted as much when he said Russia would not give up its new systems without U.S. action on addressing Russian missile defense concerns.8 Although Arbatov was talking specifically about the Sarmat and Burevestnik systems, the same logic applies to the related Avangard system and even to the Kinzhal and Tsirkon systems if they are placed on longer-range delivery mechanisms.
Recommendation #4: Prioritize Spending Strategically
While the threat posed by Russian hypersonic missiles is limited, the U.S. should ensure its defense spending counters the most threatening aspects of such systems. It is just as important that U.S. defense spending not be misspent on efforts that will not realistically mitigate the threat posed by Russia’s hypersonic missile systems. It is worth noting that some of the money spent on strategic missile defense would be better spent on more reliable countermeasures to Russian hypersonics. For example, research and development on point defenses,9 especially as it relates to aircraft carriers, would be a more worthwhile investment of taxpayer money than the Ground-based Midcourse Defense, which remains notoriously unreliable,10 and increasingly expensive.11 To briefly detour to a topic outside the scope of this article, investing in point defenses and even conventional, offensive hypersonic missiles also has the benefit of potentially countering Chinese anti-ship weaponry, including hypersonic missiles, in areas like the Taiwan Strait. Furthermore, to the extent the U.S. should be concerned about the decreased alert time due to the unpredictable trajectory of hypersonic missiles, it would be advisable for the U.S. to focus more on technologies that will allow it to improve its early warning systems, rather than begin stockpiling its own nuclear-armed hypersonic missiles.
Russia’s development of these new systems is ominous in a number of ways. Not only does it demonstrate the Kremlin’s continued reliance on nuclear weapons, it also sends a deleterious signal to the rest of the world just ahead of the rescheduled 2021 Non-Proliferation Treaty Review Conference (NPT RevCon). Efforts by the United States to rein in the nuclear aspects of these systems could bolster confidence among Non-Nuclear Weapons States that the two nuclear superpowers have not forgotten their commitment under the NPT to “undertake effective measures in the direction of nuclear disarmament.”12 As if the stakes for the 2021 NPT RevCon were not high enough already, the U.S. and Russia should have the added motivation of redressing the grievances expressed by the signatories to the Treaty on the Prohibition of Nuclear Weapons (TPNW), or Nuclear Ban Treaty. Failure by the nuclear superpowers to deliver meaningful progress towards their NPT commitments will only increase the popularity of the TPNW, which both Washington and Moscow disparage as an unwelcome distraction from the NPT regime.
Nuclear-capable hypersonic systems are inherently alarming. No one should be comfortable with the prospect of nuclear warheads flying five times the speed of sound as merely one shot in a conflict that could kill untold millions of people. However, while terrifying in their own right, the Russian hypersonic systems discussed here only underscore the threat of nuclear conflict – a threat that has existed for decades. They exacerbate existing dangers, sometimes in intriguing ways, but do not fundamentally reshape the seemingly always perilous U.S.-Russian strategic relationship. The U.S. retains several options to respond to these systems prudently. It should confront these systems rationally, recognizing that they are only part of a much larger threat.
 Pranay Vaddi and James Acton, “Proportionate Deterrence: A Model Nuclear Posture Review.” Carnegie
Endowment for International Peace, October 2, 2020. https://carnegieendowment.org/2020/10/02/restart-for-u.s.-russian-nuclear-arms-control-enhancing-security-through-cooperation-pub-82705.
 James M. Acton, “Is It A Nuke? Pre-Launch Ambiguity and Inadvertent Escalation.” Carnegie Endowment for International Peace. April 9, 2020. https://carnegieendowment.org/2020/04/09/is-it-nuke-pre-launch-ambiguity-and-inadvertent-escalation-pub-81446, p. 5.
 Dean Wilkening, “Hypersonic Weapons and Strategic Stability,” Survival, vol. 61, no. 5. October-November 2019, p. 129-148 https://nsiteam.com/social/wp-content/uploads/2020/01/Hypersonic-Weapons-and-Strategic-Stability-compressed.pdf, p. 139.
 Deputy Foreign Minister Sergey Ryabkov recently reiterated that Russia viewed dual-capable systems as part of its deterrence. See “Keynote Address: Sergey Ryabkov,” 2021 Carnegie Endowment For International Peace Nuclear Policy Conference, 6/22/21. https://ceipfiles.s3.amazonaws.com/pdf/Sergey+Ryabkov+Keynote_Transcript.pdf?mkt_tok=MDk1LVBQVi04MTMAAAF-RJ8dSauBWFD2n_ve5u0Cj1wxVr-SoKMkOICGL1WNwmHJ9Uqak-qSion57tARNYjL4-yuuFXlHM1FoyZO3FutU-xTz5ND3N32VqHiMMdM6-GQdg.
 A proposal from James Acton, interview with Michelle Dover. Press The Button, podcast audio. September 15, 2020. https://pressthebutton.libsyn.com/2020/09 0:21:40.
 “65 National Security Leaders Urge President Biden to Put Missile Defense on the Table,” Council for a Livable World. June 3, 2021. https://livableworld.org/63-national-security-leaders-urge-president-biden-to-put-missile-defense-on-the-table/.
 Austin Long, “Red Glare: The Origin And Implications Of Russia’s ‘New’ Nuclear Weapons,” War on the Rocks. March 26, 2018. https://warontherocks.com/2018/03/red-glare-the-origin-and-implications-of-russias-new-nuclear-weapons/.  Pranay Vaddi, James Acton, and Alexey Arbatov “A ReSTART for U.S.-Russian Nuclear Arms Control: Enhancing Security Through Cooperation.” Carnegie Endowment for International Peace, October 14, 2020. https://www.youtube.com/watch?v=3pjZpIZyW8U 28:11.
 Dean Wilkening, “Conventional Prompt Strike in 2030 and Beyond,” In Roberts, Brad ed. Fit For Purpose? The U.S. Strategic Posture In 2030 And Beyond, Center for Global Security Research, Lawrence Livermore National Laboratory, October 2020. https://cgsr.llnl.gov/content/assets/docs/The-US-Strategic-Posture-in-2030-and-Beyond.pdf, p. 56.
 “Fact Sheet: Ballistic Missile Defense Intercept Flight Test Record,” Missile Defense Agency. June 2021. https://www.mda.mil/global/documents/pdf/testrecord.pdf.
 Jen Judson, “Next-gen intercontinental ballistic missile interceptor estimated cost? Nearly $18B,” Defense News. April 27, 2021. https://www.defensenews.com/pentagon/2021/04/27/next-gen-intercontinental-ballistic-missile-interceptor-estimated-to-cost-nearly-18-billion/.
 Treaty on the Non-Proliferation of Nuclear Weapons, United Nations Office for Disarmament Affairs, July 1, 1968. https://www.un.org/disarmament/wmd/nuclear/npt/text.